_function_adaptors.h

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/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Copyright (c) 1996-1998
 * Silicon Graphics Computer Systems, Inc.
 *
 * Copyright (c) 1997
 * Moscow Center for SPARC Technology
 *
 * Copyright (c) 1999
 * Boris Fomitchev
 *
 * Copyright (c) 2000
 * Pavel Kuznetsov
 *
 * Copyright (c) 2001
 * Meridian'93
 *
 * This material is provided "as is", with absolutely no warranty expressed
 * or implied. Any use is at your own risk.
 *
 * Permission to use or copy this software for any purpose is hereby granted
 * without fee, provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 *
 */

/* NOTE: This is an internal header file, included by other STL headers.
 *   You should not attempt to use it directly.
 */

// This file has noo macro protection as it is meant to be included several times
// from other header.
// Adaptor function objects: pointers to member functions.

// There are a total of 16 = 2^4 function objects in this family.
//  (1) Member functions taking no arguments vs member functions taking
//       one argument.
//  (2) Call through pointer vs call through reference.
//  (3) Member function with void return type vs member function with
//      non-void return type.
//  (4) Const vs non-const member function.

// Note that choice (3) is nothing more than a workaround: according
//  to the draft, compilers should handle void and non-void the same way.
//  This feature is not yet widely implemented, though.  You can only use
//  member functions returning void if your compiler supports partial
//  specialization.

// All of this complexity is in the function objects themselves.  You can
//  ignore it by using the helper function mem_fun and mem_fun_ref,
//  which create whichever type of adaptor is appropriate.

_STLP_BEGIN_NAMESPACE

//This implementation will only be used if needed, that is to say when there is the return void bug
//and when there is no partial template specialization
#if defined (_STLP_DONT_RETURN_VOID) && defined (_STLP_NO_CLASS_PARTIAL_SPECIALIZATION) && defined (_STLP_MEMBER_TEMPLATE_CLASSES)

template<class _Result, class _Tp>
class _Mem_fun0_ptr : public unary_function<_Tp*, _Result> {
protected:
  typedef _Result (_Tp::*__fun_type) ();
  explicit _Mem_fun0_ptr(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(_Tp* __p) const { return (__p->*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Result, class _Tp, class _Arg>
class _Mem_fun1_ptr : public binary_function<_Tp*,_Arg,_Result> {
protected:
  typedef _Result (_Tp::*__fun_type) (_Arg);
  explicit _Mem_fun1_ptr(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(_Tp* __p, _Arg __x) const { return (__p->*_M_f)(__x); }

private:
  __fun_type _M_f;
};

template<class _Result, class _Tp>
class _Const_mem_fun0_ptr : public unary_function<const _Tp*,_Result> {
protected:
  typedef _Result (_Tp::*__fun_type) () const;
  explicit _Const_mem_fun0_ptr(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(const _Tp* __p) const { return (__p->*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Result, class _Tp, class _Arg>
class _Const_mem_fun1_ptr : public binary_function<const _Tp*,_Arg,_Result> {
protected:
  typedef _Result (_Tp::*__fun_type) (_Arg) const;
  explicit _Const_mem_fun1_ptr(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(const _Tp* __p, _Arg __x) const {
    return (__p->*_M_f)(__x); }

private:
  __fun_type _M_f;
};

template<class _Result, class _Tp>
class _Mem_fun0_ref : public unary_function<_Tp,_Result> {
protected:
  typedef _Result (_Tp::*__fun_type) ();
  explicit _Mem_fun0_ref(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(_Tp& __p) const { return (__p.*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Result, class _Tp, class _Arg>
class _Mem_fun1_ref : public binary_function<_Tp,_Arg,_Result> {
protected:
  typedef _Result (_Tp::*__fun_type) (_Arg);
  explicit _Mem_fun1_ref(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(_Tp& __p, _Arg __x) const { return (__p.*_M_f)(__x); }

private:
  __fun_type _M_f;
};

template<class _Result, class _Tp>
class _Const_mem_fun0_ref : public unary_function<_Tp,_Result> {
protected:
  typedef _Result (_Tp::*__fun_type) () const;
  explicit _Const_mem_fun0_ref(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(const _Tp& __p) const { return (__p.*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Result, class _Tp, class _Arg>
class _Const_mem_fun1_ref : public binary_function<_Tp,_Arg,_Result> {
protected:
  typedef _Result (_Tp::*__fun_type) (_Arg) const;
  explicit _Const_mem_fun1_ref(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator ()(const _Tp& __p, _Arg __x) const { return (__p.*_M_f)(__x); }

private:
  __fun_type _M_f;
};

template<class _Result>
struct _Mem_fun_traits {
  template<class _Tp>
  struct _Args0 {
    typedef _Mem_fun0_ptr<_Result,_Tp>            _Ptr;
    typedef _Const_mem_fun0_ptr<_Result,_Tp>      _Ptr_const;
    typedef _Mem_fun0_ref<_Result,_Tp>            _Ref;
    typedef _Const_mem_fun0_ref<_Result,_Tp>      _Ref_const;
  };

  template<class _Tp, class _Arg>
  struct _Args1 {
    typedef _Mem_fun1_ptr<_Result,_Tp,_Arg>       _Ptr;
    typedef _Const_mem_fun1_ptr<_Result,_Tp,_Arg> _Ptr_const;
    typedef _Mem_fun1_ref<_Result,_Tp,_Arg>       _Ref;
    typedef _Const_mem_fun1_ref<_Result,_Tp,_Arg> _Ref_const;
  };
};

template<class _Arg, class _Result>
class _Ptr_fun1_base : public unary_function<_Arg, _Result> {
protected:
  typedef _Result (*__fun_type) (_Arg);
  explicit _Ptr_fun1_base(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator()(_Arg __x) const { return _M_f(__x); }

private:
  __fun_type _M_f;
};

template <class _Arg1, class _Arg2, class _Result>
class _Ptr_fun2_base : public binary_function<_Arg1,_Arg2,_Result> {
protected:
  typedef _Result (*__fun_type) (_Arg1, _Arg2);
  explicit _Ptr_fun2_base(__fun_type __f) : _M_f(__f) {}

public:
  _Result operator()(_Arg1 __x, _Arg2 __y) const { return _M_f(__x, __y); }

private:
  __fun_type _M_f;
};

template<class _Result>
struct _Ptr_fun_traits {
  template<class _Arg> struct _Args1 {
    typedef _Ptr_fun1_base<_Arg,_Result> _Fun;
  };

  template<class _Arg1, class _Arg2> struct _Args2 {
    typedef _Ptr_fun2_base<_Arg1,_Arg2,_Result> _Fun;
  };
};

/* Specializations for void return type */
template<class _Tp>
class _Void_mem_fun0_ptr : public unary_function<_Tp*,void> {
protected:
  typedef void (_Tp::*__fun_type) ();
  explicit _Void_mem_fun0_ptr(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(_Tp* __p) const { (__p->*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Tp, class _Arg>
class _Void_mem_fun1_ptr : public binary_function<_Tp*,_Arg,void> {
protected:
  typedef void (_Tp::*__fun_type) (_Arg);
  explicit _Void_mem_fun1_ptr(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(_Tp* __p, _Arg __x) const { (__p->*_M_f)(__x); }

private:
  __fun_type _M_f;
};

template<class _Tp>
class _Void_const_mem_fun0_ptr : public unary_function<const _Tp*,void> {
protected:
  typedef void (_Tp::*__fun_type) () const;
  explicit _Void_const_mem_fun0_ptr(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(const _Tp* __p) const { (__p->*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Tp, class _Arg>
class _Void_const_mem_fun1_ptr : public binary_function<const _Tp*,_Arg,void> {
protected:
  typedef void (_Tp::*__fun_type) (_Arg) const;
  explicit _Void_const_mem_fun1_ptr(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(const _Tp* __p, _Arg __x) const { (__p->*_M_f)(__x); }

private:
  __fun_type _M_f;
};

template<class _Tp>
class _Void_mem_fun0_ref : public unary_function<_Tp,void> {
protected:
  typedef void (_Tp::*__fun_type) ();
  explicit _Void_mem_fun0_ref(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(_Tp& __p) const { (__p.*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Tp, class _Arg>
class _Void_mem_fun1_ref : public binary_function<_Tp,_Arg,void> {
protected:
  typedef void (_Tp::*__fun_type) (_Arg);
  explicit _Void_mem_fun1_ref(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(_Tp& __p, _Arg __x) const { (__p.*_M_f)(__x); }

private:
  __fun_type _M_f;
};

template<class _Tp>
class _Void_const_mem_fun0_ref : public unary_function<_Tp,void> {
protected:
  typedef void (_Tp::*__fun_type) () const;
  explicit _Void_const_mem_fun0_ref(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(const _Tp& __p) const { (__p.*_M_f)(); }

private:
  __fun_type _M_f;
};

template<class _Tp, class _Arg>
class _Void_const_mem_fun1_ref : public binary_function<_Tp,_Arg,void> {
protected:
  typedef void (_Tp::*__fun_type) (_Arg) const;
  explicit _Void_const_mem_fun1_ref(__fun_type __f) : _M_f(__f) {}

public:
  void operator ()(const _Tp& __p, _Arg __x) const { (__p.*_M_f)(__x); }

private:
  __fun_type _M_f;
};

_STLP_TEMPLATE_NULL
struct _Mem_fun_traits<void> {
  template<class _Tp> struct _Args0 {
    typedef _Void_mem_fun0_ptr<_Tp>             _Ptr;
    typedef _Void_const_mem_fun0_ptr<_Tp>       _Ptr_const;
    typedef _Void_mem_fun0_ref<_Tp>             _Ref;
    typedef _Void_const_mem_fun0_ref<_Tp>       _Ref_const;
  };

  template<class _Tp, class _Arg> struct _Args1 {
    typedef _Void_mem_fun1_ptr<_Tp,_Arg>        _Ptr;
    typedef _Void_const_mem_fun1_ptr<_Tp,_Arg>  _Ptr_const;
    typedef _Void_mem_fun1_ref<_Tp,_Arg>        _Ref;
    typedef _Void_const_mem_fun1_ref<_Tp,_Arg>  _Ref_const;
  };
};

template<class _Arg>
class _Ptr_void_fun1_base : public unary_function<_Arg, void> {
protected:
  typedef void (*__fun_type) (_Arg);
  explicit _Ptr_void_fun1_base(__fun_type __f) : _M_f(__f) {}

public:
  void operator()(_Arg __x) const { _M_f(__x); }

private:
  __fun_type _M_f;
};

template <class _Arg1, class _Arg2>
class _Ptr_void_fun2_base : public binary_function<_Arg1,_Arg2,void> {
protected:
  typedef void (*__fun_type) (_Arg1, _Arg2);
  explicit _Ptr_void_fun2_base(__fun_type __f) : _M_f(__f) {}

public:
  void operator()(_Arg1 __x, _Arg2 __y) const { _M_f(__x, __y); }

private:
  __fun_type _M_f;
};

_STLP_TEMPLATE_NULL
struct _Ptr_fun_traits<void> {
  template<class _Arg> struct _Args1 {
    typedef _Ptr_void_fun1_base<_Arg> _Fun;
  };

  template<class _Arg1, class _Arg2> struct _Args2 {
    typedef _Ptr_void_fun2_base<_Arg1,_Arg2> _Fun;
  };
};

// pavel: need extra level of inheritance here since MSVC++ does not
// accept traits-based fake partial specialization for template
// arguments other than first

template<class _Result, class _Arg>
class _Ptr_fun1 :
  public _Ptr_fun_traits<_Result>::_STLP_TEMPLATE _Args1<_Arg>::_Fun {
protected:
  typedef typename _Ptr_fun_traits<_Result>::_STLP_TEMPLATE _Args1<_Arg>::_Fun _Base;